Had one year before last, one of my last jobs before I moved to CID. The car driver was built like giant haystack, absolutely dwarfed me, and with one punch put the teeth down the cyclists throat, knocked him out and left him covered in abrasions where he hit the floor. The driver went guilty in court, but claimed the mitigation that he thought the cyclist was about to lump him and walked away with a Court issues caution. The cyclist was stretchers away needing hundreds in dental work.
When you've spent 18 years in roads policing, and 6 of those specialising in incidents involving cyclists you'll have seen plenty of road rage, and rarely does the person starting it walk away the victor in any sense of the word. I've seen guys put fists through car window glass and punch drivers in one fluid movement. Overseen drivers take baseball bats and knives to their antagonists. I dealt with one where the driver was shot.
Before getting into a confrontation just think Kenneth Noye. There is always someone out there more willing than you to use violence, less inhibited than you about the levels of violence they will use. Anyone who yawps off like the cyclist in the video is quite simply an idiot.